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Integrative Zoology 2013年第3期8卷 307-314页

作者： Glauco b.O.MACHADO joão b.L.GUSMÃO-JUNIOR tânia M.COStA Campus Experimental do Litoral Paulista UNESPSão VicenteSão PauloBrazil

the continuous excavation of burrows by fiddler crabs generates bioturbation in the sediment,which can be estimated from burrow *** aim of the present study was to describe the burrow morphology of Uca uruguayensis and *** and its relationship with demography of resident individuals and to estimate the level of bioturbation in the sediment generated by each *** all individuals from each of the 2 species,sex was determined and the carapace width(CW;mm)*** were characterized according to burrow diameter(bD;mm),maximum burrow depth(MbD;mm)and burrow volume(bV;cm^(3)).the density of each species in the study area was also *** both species,the males were larger and occupied burrows with higher bV compared to *** between sexes in relation to the burrow characteristics might reflect sexual dimorphism within the group and are probably related to the fact that males use the burrows for *** and bV showed significant positive relationships with the size of resident *** amount of sediment removed per burrow was estimated from mean bV:10.78 cm^(3)of sediment/burrow for *** and 12.38 cm^(3)of sediment/burrow for *** the density and depth differences between the 2 species,the similarity in burrow volume suggests that *** and *** present the same importance in terms of the bioturbation *** morphology is highly associated with characteristics of the occupant,although extrinsic factors should also be considered,and its description can provide estimates on the bioturbation generated by Uca species in mangrove forests.

关键词： bioturbation burrow structure crab burrowing fiddler crab

Flotation and surface modification characteristics of galena,sphalerite and pyrite in collecting-depressing-reactivating system

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journal of Central South University 2012年第6期19卷 1702-1710页

作者： t.H.PAK 孙体昌徐承焱 Y.H.jo School of Civil and Environment Engineering University of Science and Technology Beijing School of Mining Engineering University of Mining and Metallurgy Chongjin

the flotation tests and XPS analyses on galena,sphalerite and pyrite have been carried out in a collecting-depressing-reactivating system(hereafter referred as the CDR system).In this system,sulfide minerals were first collected and activated by the collector,and then depressed strongly by Ca(OH)2 in the strong alkaline solution,and finally reactivated by *** flotation tests of pure minerals show that in this system the flotation behaviors of sphalerite and pyrite present irreversible characteristics along with the change of pulp ***,through the CDR system,considerable differences in the flotabilities between galena and sphalerite/pyrite are also *** XPS analysis results for galena,sphalerite and pyrite in a CDR system show that in the strong alkaline solution,some of the collectors,that have been already adsorbed on the mineral surface in the collecting process,are desorbed by Ca(OH)*** XPS analysis results also show that in H2SO4 reactivating process,the surface hydroxides of galena are desorbed again by H2SO4 and replaced by diethyl dithiocarbamate,but those of sphalerite and pyrite are not *** flotation system may be applied to the bulk-differential flotation process of sulfur-bearing low-grade lead-zinc ores.

关键词： CDR system XPS analysis galena sphalerite pyrite

Measuring vacuum polarization with high-power lasers

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High Power Laser Science and Engineering 2016年第1期4卷 29-40页

作者： b.King t.Heinzl Centre for Mathematical Sciences Plymouth University

When exposed to intense electromagnetic fields, the quantum vacuum is expected to exhibit properties of a polarizable medium akin to a weakly nonlinear dielectric material. Various schemes have been proposed to measure such vacuum polarization effects using a combination of high- power lasers. Motivated by several planned experiments, we provide an overview of experimental signatures that have been suggested to confirm this prediction of quantum electrodynamics of real photon–photon scattering.

关键词： Heisenberg–Euler photon–photon scattering vacuum birefringence vacuum polarization

A new adaptive bending method using closed loop feedback control

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transactions of Nonferrous Metals Society of China 2010年第11期20卷 2111-2117页

作者： t.WELO b.GRANLY Department of Engineering Design and Materials Norwegian University of Science and Technology(NTNU)

As the competition from companies in low cost countries increases,the need for more automated production which reduces labour cost while improving product quality is required.A new rotary compression bending set-up with automated closed-loop feedback control is thus being *** transferring in-process measurement data into an algorithm for predicting springback and bend angle prior to the unloading sequence,the dimensional accuracy is *** work focuses on the development of this steering *** the method used does not increase cycle time,it is attractive for high-volume industrial *** than 150 bending tests of AA6060 extrusions were conducted to determine the capability of the *** results show that by activating the automated closed-loop feedback system,the dimensional accuracy of the bent parts is more than three times better than that obtained by traditional compression *** the steering model permits the direct use of additional process data,such as instant wall thickness and cross sectional distortions,it is believed that extension of the measurement capabilities would improve the accuracy of the methodology even further.

关键词： adaptive bending closed-loop feedback dimensional accuracy springback aluminium extrusion

CompactChain:an efficient stateless chain for UtXO-model blockchain

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Frontiers of Computer Science 2024年第2期18卷 167-179页

作者： b Swaroopa REDDY t Uday Kiran REDDY Department of Electrical Engineering Indian Institute of Technology HyderabadHyderabadTelangana 502285India

In this work,we propose a stateless blockchain called CompactChain,which compacts the entire state of the UtXO(Unspent transaction Output)based blockchain systems into two RSA *** first accumulator is called transaction Output(tXO)commitment which represents the tXO *** second one is called Spent transaction Output(StXO)commitment which represents the StXO *** this work,we discuss three algorithms:(i)to update the tXO and StXO commitments by the *** miner also provides the proofs for the correctness of the updated commitments;(ii)to prove the transaction’s validity by providing a membership witness in tXO commitment and non-membership witness against StXO commitment for a coin being spent by a user;(iii)to update the witness for the coin that is not yet spent;the experimental results evaluate the performance of the CompactChain in terms of time taken by a miner to update the commitments and time taken by a validator to verify the commitments and validate the *** compare the performance of CompactChain with the existing state-of-the-art works on stateless *** shows a reduction in commitments update complexity and transaction witness size which inturn reduces the mempool size and propagation latency without compromising the system throughput(transactions per second(tPS)).

关键词： stateless blockchain RSA Accumulator StXO commitment tXO commitment UtXO Non-interactive Proof of Exponentiation(NI-PoE) transactions per second(tPS)

An Adaptive Load Stepping Algorithm for Path-Dependent Problems based on estimated Convergence Rates

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Computer Modeling in Engineering & Sciences 2017年第3期113卷 325-342页

作者： M.t.C.Araújo Fernandes C.O.Cardoso W.J.Mansur Civil Engineering Department/COPPE/Federal University of Rio de Janeiro Ilha do FundaoP.B.6850621945-970 Rio de JaneiroRJBrazil Petrobras/Cenpes Av.Horácio Macedo950Ilha do Fundao21941-915 Rio de JaneiroRJBrazil Civil Engineering Department/COPPE/Federal University of Rio de Janeiro Ilha do FundaoP.B.6850621945-970 Rio de JaneiroRJBrazil

A new adaptive(automatic)time stepping algorithm,called RCA(Rate of Convergence Algorithm)is *** new algorithm was applied in nonlinear finite element analysis of path-dependent *** step size is adjusted by monitoring the estimated convergence rate of the nonlinear iterative *** RCA algorithm is relatively simple to implement,robust and its performance is comparable to,and in some cases better than,the automatic load incrementaion algorithm existent in commercial *** about the convergence rate of nonlinear iterative processes,an estimation of the rate and a study of the parameters of the RCA algorithm are *** show the capacity of the algorithm to adjust the increment size,detailed discussions based on results for different limit load analyses are *** results obtained by RCA algorithm are compared with those by AbAQUS?,one of the most powerful nonlinear FEA(Finite Element Analysis)commercial software,in order to verify the capability of RCA algorithm to adjust the increment size along nonlinear analyses.

关键词： Rate of convergence nonlinear automatic load incrementation limit load

Exact solutions to drift-flux multiphase flow models through Lie group symmetry analysis

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Applied Mathematics and Mechanics(English Edition) 2015年第8期36卷 1105-1112页

作者： b.bIRA t.R.SEKHAR Department of Mathematics National Institute of Science and Technology Department of Mathematics Indian Institute of Technology Kharagpur

In the present paper, Lie group symmetry method is used to obtain some exact solutions for a hyperbolic system of partial differential equations （PDes）, which governs an isothermal no-slip drift-flux model for multiphase flow problem. those sym- metries are used for the governing system of equations to obtain infinitesimal transforma- tions, which consequently reduces the governing system of PDes to a system of ODes. Further, the solutions of the system of ODes which in turn produces some exact solutions for the PDes are presented. Finally, the evolutionary behavior of weak disco.tinuity is discussed.

关键词： multiphase flow drift-flux models Lie group analysis exact solution weakdisco.tinuity

A note on general solution of Stokes equations

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Acta Mechanica Sinica 2016年第6期32卷 1044-1045页

作者： b.Sri Padmavati t.Amaranath School of Mathematics & Statistics University of Hyderabad

Li et al. (2015) claim that it is sufficient to use two harmonic functions to express the general solution of Stokes equations. In this paper, we demonstrate that this is not true in a general case and that we in fact need three scalar harmonic functions to represent the general solution of Stokes equations (Venkatalaxmi et al., 2004).

关键词： Stokes equations General solution Harmonic functions

tuning MXenes towards their Use in Photocatalytic Water Splitting

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Energy & Environmental Materials 2024年第6期7卷 321-331页

作者： Diego Ontiveros Sergi Vela Francesc Viñes Carmen Sousa Departament de Ciència de Materials i Química Física&Institut de Química teòrica i Computacional(IQtCUb) Universitat de Barcelonac/Martíi Franquès 1-1108028 BarcelonaSpain

Finding appropriate photocatalysts for solar-driven water(H_(2)O)splitting to generate hydrogen(H_(2))fuel is a challenging task,particularly when guided by conventional trial-and-error experimental ***,density functional theory(DFt)is used to explore the MXenes photocatalytic properties,an emerging family of two-dimensional(2D)transition metal carbides and nitrides with chemical formula M_(n+1)X_(n)t_(x),known to be semiconductors when having t_(x)*** than 4,000 MXene structures have been screened,considering different compositional(M,X,t_(x),and n)and structural(stacking and termination position)factors,to find suitable MXenes with a bandgap in the visible region and band edges that align with the water-splitting half-reaction *** from bandgap analysis show how,in general,MXenes with n=1 and transition metals from group III present the most cases with bandgap and promising sizes,with C-MXenes being superior to *** band alignment calculations of candidate systems with a bandgap larger than 1.23 eV,the minimum required for a water-splitting process,Sc_(2)Ct_(2),Y_(2)Ct_(2)(t_(x)=Cl,br,S,and Se)and Y_(2)CI_(2)are highlighted as adequate photocatalysts.

关键词： Density Functional theory MXenes Photocatalysis Water Splitting

Reaction of diaminoglyoxime and cyclic azine compounds in high temperature and pressure water

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Chinese Science bulletin 1998年第16期43卷 1395-1399页

作者： t.b.brill Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Department of Chemistry and biochemistry University of Delaware Newark USA

Diaminoglyoxime was reacted in water at 150-400℃ and at 27.5 MPa pressure in metal ti tubing reactor. Experimental results indicate that, diaminoglyoxime can be converted into NH-3 and CO-2, either through direct hydrolysis or through pyrolysis and polymerization, and then further hydrolysis. the possible reaction mechanism is nucleophilic addition of water.

关键词： diaminoglyoxime cyclic azine compound supercritical water pyrolysis hydrolysis organic wastes.